U.S. Pat. No. 2,488,188 of Halvorson, U.S. Pat. No. 2,534,061 of Rogers, U.S. Pat. No. 2,738,585 of Vissing, U.S. Pat. No. 2,849,795 of Vissing, U.S. Pat. No. 3,831,285 of Vissing, U.S. Pat. No. 5,495,676 of Chestnut et al., U.S. Pat. No. 6,416,189 of Watson, U.S. Pat. No. 6,799,854 of Steiner, U.S. Pat. No. 6,811,268 of Watson and D445,475 of Spear describe various pivoting lens caps for riflescopes and telescopic sights. The present inventor has recognized disadvantages of these designs and has identified a need for an improved pivoting lens cap having a durable weather-tight construction.